Apparatus for wet processing of textile fabrics

ABSTRACT

In an apparatus for wet processing of textile fabrics, a vessel of elongated and substantially straight tubular form is slightly inclined to a horizontal plane and contains a similarly inclined open-ended conduit and a length of fabric to be treated is led down through the conduit and then in a multi-looped arrangement back up the vessel and joined in endless form to re-enter the conduit. The vessel contains treatment liquid and this is forcefully projected down the conduit to transport the fabric therethrough and thereby cause the fabric to circulate through the vessel. Liquid may also be projected against the fabric leaving its multi-looped arrangement. Preferably the crosssectional shape of the conduit becomes progressively broader and flatter approaching its outlet end.

United States Patent 1191 Marsh et a1.

1 1 Oct. 2, 1973 1 1 APPARATUS FOR WET FROCESSING 0F TEXTILE FABRICS [75 lnven tor s z Frank Hubert Marsh, Scarcroft, nr.

Leeds; James Kevin Hegarty, Leeds, both of England [7 3 '1 Assigii': Plat? Manama lfniited. Leeds,

England [22] Filed: Mar. 13, 1972 [21] Appl No.: 234,222

Primary ExaminerWilliam 1. Price A!t0rneyWolf, Greenfield & Sacks [57] ABSTRACT In an apparatus for wet processing of textile fabrics, a vessel of elongated and substantially straight tubular form is slightly inclined to a horizontal plane and contains a similarly inclined open-ended conduit and a length of fabric to be treated is led down through the conduit and then in a multi-looped arrangement back up the vessel and joined in endless form to re-enter the conduit. The vessel contains treatment liquid and this is forcefully projected down the conduit to transport the fabric therethrough and thereby cause the fabric to circulate through the vessel. Liquid may also be projected against the fabric leaving its multi-looped arrangement. Preferably the cross-sectional shape of the conduit becomes progressively broader and flatter approaching its outlet end.

6 Claims, 6 Drawing Figures PAIENIEnucr 'zms' 3762.189 sum 10F 2 APPARATUS FOR WET PROCESSING OF TEXTILE FABRICS This invention relates to apparatus for the wet processing of textile fabrics, for example dyeing or scouring, and will be referred to hereinafter in relation to dyeing.

The invention concerns that type of apparatus in which a length of fabric in endless form can be circulated through a bath of treatment liquid by the propelling action of a pressurized flow of fluid along a restricted passage forming part of the circulatory path of the fabric.

Apparatus of this type as at present known or used has one or more of the following disadvantages.

1. Dimensional instability of fabric. This is caused because the only force which is exerted on the fabric during the wet processing is a longitudinal pull which tends to stretch the fabric, and consequently make it narrower. During a subsequent heat finishing process, the fabric is pulled back to give the desired width. The original wet setting can overcome the subsequent dry setting, in time and after use, and can result in a misshaped garment made up from the fabric.

2. Poor yield of fabric. This is a second result of the problem mentioned in (l), where, because of stretching two ways, the resultant weight of the fabric per square metre is reduced.

3. Crease and crush marking. These are caused by:

a. allowing the fabric to stay in a close rope form b. compacting the material too much within the bath.

Apparatus having upright U or J shaped baths obviously require a pressure to push the fabric around the lower bend, which causes compacting. This condition is further aggravated by the varying specific gravity of the fabric being processed throughout the processing temperature range; this also leads to problems with straight baths situated either vertically or horizontally, giving compacting of the fabric at the top or bottom of the bath, depending upon the relative specific gravity of the fabric being processed.

4. The handle or degree of softness or hardness of fabric to the touch can be affected by whether or not the fabric is allowed to pass through air on each circuit through the apparatus. A handle on the soft side is achieved by keeping the fabric submereged under the treating liquid, and a crisper fabric can be had by allowing the fabric to breathe air at some point in its circuit through the apparatus. All of the machines that we know can give either one condition or the other, but not both.

With a view to overcoming or reducing the seriousness of some or all of the above mentioned disadvantages, an apparatus according to the present invention includes a bath or vessel of generally elongated and substantially straight tubular form mounted with its longitudinal or major axis slightly inclined to a horizontal plane, an open-ended conduit within the vessel extending longitudinally of the bath near the underside thereof and with a similar inclination, means for leading an endless length of fabric through said conduit in the downwardly inclined direction to the lower end of the bath and then in a multi-looped arrangement back through the bath to the upper end thereof to re-enter the conduit, and means for projecting treatment liquid under pressure down the conduit to transport the fabric therethrough and to cause the fabric to be circulated through the bath.

The inclination of the bath and conduit will be within the range 5 to 30 and preferably of the order of 10, and the term slightly inclined" in this context in the description and in the appended claims is to be interpreted in this sense.

Means are preferably provided for pumping treatment liquid into the upper part of the bath as well as for projecting it into the upper end of the conduit to transport the fabric down the latter, the liquid being taken from the lower part of the bath for re-circulation. In this context the terms upper part" and lower part" relate to the inclination of the vessel. Thus, the fabric in its multi-looped arrangement is treated both by the downward flow in the upper part of the bath and by the upward flow of the liquid issuing from the conduit into the lower part of the bath.

The conduit may be of any suitable cross-section and may become more broadened and flattened towards the lower end for a purpose described below.

While it is commercially most convenient for the vessel to be of straight tubular form, one which is slightly curved in the longitudinal or major axis direction might be used if desired.

The top level of the treatment liquid can be controlled so that either the fabric remains immersed during the whole of its treatment or alternatively the fabric emerges from the liquid so as to be exposed to air before re-entering the conduit.

One form of apparatus according to the invention is illustrated merely by way of example in the accompanying drawings wherein:

FIG. 1 represents schematically a side elevation of the apparatus showing the formation taken by the fabric as it is circulated through the liquid bath in the vessel;

FIGS. 2 and 3 are examples of the comparative crosssectional shapes which may be used for upper and lower parts of a conduit extending along the vessel, the sections being taken respectively on the lines A-A and B-B in FIG. 1;

FIG. 4 is a sectional elevation of the upper end of the conduit and of means indicated in FIG. 1, for delivering the treatment liquid thereto and to the upper end of the vessel;

FIG. 5 is an end view seen in the direction of arrow X in FIG. 4; and

FIG. 6 is an outline plan of the vessel indicated in FIG. 1 showing the position and preferred shape of the conduit.

Arrows in the drawings indicate the direction of flow of liquid in the apparatus.

Referring mainly to FIG. 1 of the drawings, the bath is shown as a straight tubular closed vessel 1 supported at an inclination of about 10 to a horizontal plane. Its upper end has a closable opening 2 for introduction and removal of the fabric F and adjacent this end is a winch 3 for handling the fabric. Also adjacent this end on the top of the vessel is shown a connection 4 for introduction of compressed air, this connection having a pressure release valve 5, but this would only be required if it was desired to pressurize the vessel for certain applications.

In this example a hot treatment liquid is supplied to the upper end portion of the vessel by a main pump 6 via a heat exchanger 7, jet throttle 8 and inlet pipe 9,

and this liquid is withdrawn from the lower portion of the vessel by the pump via an outlet pipe 10, isolating valve 11 and filter 12, the filter also being connected through a pipe 13 and auxiliary isolating valve 14 with the lowermost part of the vessel for use when the vessel is to be drained through a drain valve 15. The pump 6 can also be connected to a water supply when required through a valve 16. The valved outlet 17 is for use in continuous overflow rinsing. The pumping and liquid circulating means described above may have associated therewith auxiliary equipment such as is normally provided in installations for the wet processing of textile fabrics, but these need no further reference since they form no part of the present invention.

A conduit 18 extends along the vessel supported parallel to the belly or underside of the vessel so as to have approximately the same general inclination as the latter but to be spaced from the wall thereof. The upper end of the conduit has a mouth portion 19 inclined more steeply upwards (see FIG. 4) and the conduit varies progressively in cross-sectional shape from near the upper end to near the lower end as indicated in FIGS. 2 and 3. At the lower (outlet) end where the conduit has become flattened and widened as in FIG. 3, it is curved upwards and back on itself at 20 so that the outlet is directed to face up the vessel, the width of the conduit and its cross-sectional area preferably increasing throughout this curved portion, this increase in area facilitating the passage of fabric round the curve without objectionably crushing the fabric.

The length of fabric F to be treated is fed through the opening 2 into the mouth 19, threaded down along the conduit 18 to emerge at the lower end thereof, and brought back up the vessel and around a freely rotatable guide roller 21, the two ends of the fabric then being joined to form an'endless length of material many times greater than the length of the vessel.

Referring more particularly to FIGS. 4 and 5, the mouth 19 of the conduit has an inner sleeve 22 with a funnel-shaped inlet opening 23 and having in its wall a plurality of apertures 24 inclined inwardly and in the direction of flow. The annular space 25 around the sleeve 22 communicates with the liquid inlet pipe 9. The pipe 9 also communicates through a flow control valve 26 with a manifold 27 from which lead several jet pipes 28. These pipes '28 have their outlet ends directed away from the upper end of the vessel and towards perforated baffle plates 29, 30 (see FIG. 1) which are located above the conduit 18 and above which the fabric passes shortly before reaching the guide roller 21.

The lower portion of the vessel 1 has an internal cylindrical perforated guard 31 which is spaced from the vessel wall and through which iiquid is withdrawn into outlet pipe for re-circulation.

In operating the above described apparatus, the vessel is kept substantially full of liquid which is continuously pumped into the inlet end 19 of the conduit 18 at sufficient volume and velocity to transport the fabric down therethrough and out of the lower end at 20 so as to move the fabric upwards in the lower part of the bath. Liquid is also forced from the jet pipes 28 through the perforated baffle plates 29, 30 down through the upper and central part of the bath against the upward travelling fabric and liquid is continuously withdrawn from the lower part of the bath through outlet 11 to be re-circulated through the vessel.

The fabric takes up a multi-looped arrangement somewhat as illustrated in FIG. 1 during its travel up the vessel so that a long length of fabric (e.g. 550 metres) may be treated at one time in a comparatively short vessel (e.g. 4.5 metres).

The upper surface of the liquid can be maintained by any suitable level control device at a minimum level L] so that the fabric emerges into the air before reentering the conduit, or at a maximum level L2 so that the fabric is always submerged, the guide roller 21 being suitably located to permit this choice of levels.

By means of this invention the treating liquid is passed through the bulk of the fabric both from the upper and lower ends of the bath. The fact that the vessel is straight ensures that the bulk of the fabric can travel to the 'upper end without any undue pressure being exerted upon it. Moreover, since the flotational property of different fabrics will vary with the variations in their specific gravities (affected by the treatment temperatures), the inclined upper wall of the vessel will gently retard a floating fabric and prevent it from rushing to the upper end of the vessel, whilst in similar manner the inclined lower wall of the vessel and the upper surface of the conduit tend to support a sinking fabric and prevent it from compacting in the lower end of the vessel.

The progressive variation in cross-section of the conduit terminating in a broadened and flattened shape promotes the change of the fabric from a rope or bunched-together form to an opened-out form. This results in moving and opening out the longitudinal folds and creases, thereby reducing the risk of leaving crease marks in the fabric. The said cross-sectional variation exerts a gentle lateral force to the fabric, resultingin a very stable condition and also giving a high yield of fabric; it also reduces the likelihood of the fabric becoming tangled during its travel up the bath.

Whilst the hereinbefore described embodiments of the invention have been mentioned merely by way of example, it is to be understood that other suitable embodiments may be evolved for carrying out the invention and that protection is hereby claimed for all such embodiments within the scope of the appended claims.

We claim:

1. An apparatus for the wet processing of textile fabrics, including an elongated vessel of tubular form of containing treatment liquid, means for mounting said vessel with its longitudinal axis inclined at less than 45 to a horizontal plane, an open-ended conduit located within said vessel near the underside thereof and extending longitudinally thereof with a similar inclination to that of said vessel, means for leading a'length of fabric in endless form through said conduit in the downwardly inclined direction towards the lower end of said vessel and then in a multi-looped arrangement back through said vessel to the upper end thereof to re-enter said conduit, and means for projecting treatment liquid down through said conduit to transport said fabric therethrough and to cause said fabric to be circulated through said vessel.

2. An apparatus as claimed in claim 1, including means for introducing treatment liquid also into the upper part of said vessel and means for withdrawing liquid from the lower part of said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel.

3. An apparatus as claimed in claim 1, wherein the crosssectional shape of said conduit alters progressively towards its lower end by increasing in width and decreasing in depth, said lower end being curved upwards and back on itself so that its outlet is directed to face in the upwardly inclined direction of said vessel.

4. An apparatus as claimed in claim 1, including a freely rotatable guide roller located in advance of the inlet end of said conduit for guiding said fabric back into said conduit after it has left its multi-looped arrangement, said roller being capable of guiding said fabric at the upper end of its circulatory path so that at choice it either can be continually submerged during its treatment or can emerge from the liquid before reentering said conduit.

5. An apparatus as claimed in claim 1, including means for introducing treatment liquid also into the upper part of said vessel and means for withdrawing liquid from the lower part of'said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel, at least one baffle plate having a multiplicity of apertures therein and located above the upper part of said conduit so that said fabric must travel over said plate before re-entering said conduit, and means for projecting treatment liquid through said apertures and thereafter down through the upper and central part of said vessel against the upward travel of said multi-looped fabric.

6. An apparatus as-claimed in claim 1, including means for introducing treatment liquid also into the upper part of said vessel and means for withdrawing liquid from the lower part of said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel, and a sleeve located in the mouth of said conduit and having in its wall a plurality of apertures inclined inwardly and in the direction of travel of said fabric through said conduit and an annular space located between the walls of said mouth sleeve and through which said treatment liquid is projected down said conduit. 

1. An apparatus for the wet processing of textile fabrics, including an elongated vessel of tubular form of containing treatment liquid, means for mounting said vessel with its longitudinal axis inclined at less than 45* to a horizontal plane, an open-ended conduit located within said vessel near the underside thereof and extending longitudinally thereof with a similar inclination to that of said vessel, means for leading a length of fabric in endless form through said conduit in the downwardly inclined direction towards the lower end of said vessel and then in a multi-looped arrangement back through said vessel to the upper end thereof to re-enter said conduit, and means for projecting treatment liquid down through said conduit to transport said fabric therethrough and to cause said fabric to be circulated through said vessel.
 2. An apparatus as claimed in claim 1, including means for introducing treatment liquid also into the upper part of said vessel and means for withdrawing liquid from the lower part of said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel.
 3. An apparatus as claimed in claim 1, wherein the cross-sectional shape of said conduit alters progressively towards its lower end by increasing in width and decreasing in depth, said lower end being curved upwards and back on itself so that its outlet is directed to face in the upwardly inclined direction of said vessel.
 4. An apparatus as claimed in claim 1, including a freely rotatable guide roller located in advance of the inlet end of said conduit for guiding said fabric back into said conduit after it has left its multi-looped arrangement, said roller being capable of guiding said fabric at the upper end of its circulatory path so that at choice it either can be continually submerged during its treatment or can emerge from the liquid before re-entering said conduit.
 5. An apparatus as claimed in claim 1, including means for introducing treatment liquid also into the upper paRt of said vessel and means for withdrawing liquid from the lower part of said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel, at least one baffle plate having a multiplicity of apertures therein and located above the upper part of said conduit so that said fabric must travel over said plate before re-entering said conduit, and means for projecting treatment liquid through said apertures and thereafter down through the upper and central part of said vessel against the upward travel of said multi-looped fabric.
 6. An apparatus as claimed in claim 1, including means for introducing treatment liquid also into the upper part of said vessel and means for withdrawing liquid from the lower part of said vessel for re-circulation therethrough, whereby said fabric in its multi-looped arrangement is treated both by the downward flow of liquid in the upper part of said vessel and by the upward flow of liquid which issues from said conduit into the lower part of said vessel, and a sleeve located in the mouth of said conduit and having in its wall a plurality of apertures inclined inwardly and in the direction of travel of said fabric through said conduit and an annular space located between the walls of said mouth sleeve and through which said treatment liquid is projected down said conduit. 